Theorem 2.7 (see Phúc-Sum [1]}) 
All the spikes in \((P_t)_n\)  are admissible and their weight vectors are weakly decreasing. Furthermore, if a weight vector \(\omega = (\omega _1, \omega _2, \ldots )\)  is weakly decreasing and \(\omega _1\le t,\) then there is a spike \(z\in (P_t)_n\)  such that \(\omega (z) = \omega .\)

